1. Field of the Invention
The present invention relates to a film deposition apparatus and a film deposition method for depositing a film on a substrate by carrying out plural cycles of supplying in turn at least two source gases to the substrate in order to form plural layers of a reaction product, and a storage medium storing a computer program for carrying out the film deposition method.
2. Description of the Related Art
As a film deposition technique in a semiconductor fabrication process, there has been known a so-called Atomic Layer Deposition (ALD) or Molecular Layer Deposition (MLD), in which a first reaction gas is adsorbed on a surface of a semiconductor wafer (referred to as a wafer hereinafter) under vacuum and then a second reaction gas is adsorbed on the surface of the wafer in order to form one or more atomic or molecular layers through reaction of the first and the second reaction gases on the surface of the wafer, and such an alternating adsorption of the gases is repeated plural times, thereby depositing a film on the wafer. This technique is advantageous in that the film thickness can be controlled at higher accuracy by the number of times of alternately supplying the gases, and in that the deposited film can have excellent uniformity over the wafer. Therefore, this deposition method is thought to be promising as a film deposition technique that can address further miniaturization of semiconductor devices.
In order to carry out such a film deposition method, a film deposition apparatus having a vacuum chamber and a susceptor that holds plural wafers along a rotation direction of the susceptor (Patent document 1). Patent document 1 discloses a process chamber in which plural wafers are placed on a wafer support member (rotation table) at equal angular intervals along a rotation direction of the wafer support member, the wafer support member being horizontally rotated in order to deposit a film on the wafers, first and second gas ejection nozzles are located along the rotation direction and oppose the wafer support member, and purge gas nozzles that are located between the first and the second gas ejection nozzles. According to such a vacuum chamber, the purge gas nozzles create gas curtains for impeding the first and the second reaction gases from being mixed.
Patent Document 1: Japanese Patent Publication No. Japanese Patent Application Laid-Open Publication No. 2001-254181.